Forty years ago today, on the 28th of January 1986, the Space Shuttle Challenger exploded live on TV.

To the shock of the millions of people watching, the shuttle disintegrated just 73 seconds after launch... And tragically all astronauts on board were killed.

For season five of Science Friction, ABC journalist Fiona Pepper -- and co-host Dr Karl -- investigate how the Challenger disaster unfolded, and what its legacy means for science.

• GUEST: Dr Karl Kruszelnicki
• PRODUCER: Oscar Coleman